Equations

Solve the equation: 4m + 9 = 21

• m = 10

• m = 7

• m = 3

• m = 5

Answer explanation

Subtract 9 from both sides to isolate 4m: 4m = 12. Then divide by 4 to solve for m: m = 3. Therefore, the correct answer is m = 3.

Write an equation for the following word problem: If a number is divided by 4, the result is 7.

• x = 21

• x = 10

• x = 14

• x = 28

Answer explanation

To find the number, we multiply the result by the divisor: 7 * 4 = 28. Therefore, the equation is x = 28, which is the correct answer choice.

Solve the equation: 1/2 * y = 3

• y = 2

• y = 6

• y = 4

• y = 8

Answer explanation

To solve the equation 1/2 * y = 3, multiply both sides by 2 to get y = 6. Therefore, the correct answer is y = 6.

Use inverse operations to solve the equation: 3q + 4 = 19

• q = 10

• q = 6

• q = 4

• q = 5

Answer explanation

To solve the equation, first subtract 4 from both sides to isolate 3q. Then, divide by 3 to find q = 5.

Identify the variable in the equation: 4a + 2 = 10

• c

• b

• x

• a

Answer explanation

The variable in the equation is 'a' because it is multiplied by 4 in the term 4a.

Write an equation for the following word problem: If a number is doubled, the result is 16.

• 2x = 16

• x = 8

• 2x = 12

• 2x = 8

Answer explanation

The correct equation for the word problem 'If a number is doubled, the result is 16' is 2x = 16, where x represents the number.

Solve the equation: 3/4 * b = 5

• b = 20/3

• b = 25/3

• b = 4/3

• b = 15/4

Answer explanation

To solve the equation 3/4 * b = 5, multiply both sides by 4/3 to isolate b. This gives b = 20/3, which is the correct answer.

Use inverse operations to solve the equation: 5r - 3 = 22

• r = 3

• r = 15

• r = 10

• r = 5

Answer explanation

To solve the equation 5r - 3 = 22, first, add 3 to both sides to isolate 5r. This gives 5r = 25. Then, divide by 5 to find r = 5. Therefore, the correct answer is r = 5.

Solve the equation: 6s + 12 = 30

• s = 10

• s = 3

• s = 8

• s = 5

Answer explanation

To solve the equation, first subtract 12 from both sides to isolate 6s. This gives 6s = 18. Then, divide by 6 to find s = 3. Therefore, the correct answer is s = 3.

Solve for x: 3x = 21

Answer explanation

Solve for x: 3x = 21

x = 21 ÷ 3

x = 7